Clauius Ptolemaeus (Greek: Κλαύδιος Πτολεμαῖος Klaúdios Ptolemaĩos; after 83 – 161 AD), known in English as Ptolemy, was an ancient mathematician, geographer, astronomer, and astrologer. He lived in Roman Egypt, and was probably born there in a town in the Thebaid called Ptolemais Hermiou; he died in Alexandria in 161 AD.